Contactless energy transmission systems for electric energy are known in principle. By employing a transmitter coil a magnetic field is generated, that in an oppositely arranged receiver coil generates a current, that in turn is used either directly for operating an electrical device, or for charging a battery.
In general, efforts are directed at achieving an optimal coupling between the two coils or a low stray field which is emitted by the transmitter coil, in order to be able to transmit the energy efficiently. In addition, such systems shall also be electromagnetically compatible. This applies, in particular, to the charging operation of electric cars, which should be highly efficient with respect to occurring outputs; and which should not present much in the way of danger to people and animals present in the vicinity of motor vehicles. After all, strong electromagnetic fields straying over a large radius may represent health risks to humans and animals.